/*
 * Copyright (c) 2011-2012 Alexander Dubu
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * o  Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * o  Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * o  Neither the name Axil nor the names of its contributors may be used to
 *    endorse or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

package axil.definition;

import axil.api.extend.Function;
import axil.api.extend.Operator;
import axil.framework.validation.ValidationContext;
import axil.framework.xml.InputXML;
import axil.stdlib.collection.type.Range;

import java.util.List;

import static axil.framework.Functions.construct;
import static axil.framework.Functions.require;


/**
 * The XML-based definition of an Axil operator.
 */
public class OperatorDefinition extends DefinitionWithExample {
	private String symbol;
	private List<String> aliases;

	private transient Operator op;
	private transient Function func;

	public OperatorDefinition(InputXML xml) {
		super(xml);
		symbol = xml.content("symbol");
		aliases = xml.strings("aliases", "alias", Range.any);
	}


	public String symbol() {
		return require(symbol);
	}


	public List<String> aliases() {
		return aliases;
	}


	public boolean lazy() {
		return code().evaluation() == Evaluation.lazy;
	}


	public Operator operator() {
		if (op == null) {
			op = construct(Operator.class, code().classname());
		}
		return op;
	}


	public Function function() {
		if (func == null) {
			func = construct(Function.class, code().classname());
		}
		return func;
	}


	/**
	 * Validate this object in the given context. Any problems detected with the
	 * correctness or completeness of this object are placed into the context.
	 * This method descends into its owned members, validating them as well.
	 */
	public void validate(ValidationContext context) {
		super.validate(context);
		context.required("symbol", symbol);
	}
}
